Machine for cutting or slicing minerals



(No Model.) 15 Sheets-Sheet 1. W. B. DWIGHT MACHINE FOR CUTTING QR SLICING MINERALS. No. 445,983.

Patented Feb. 10,1891.

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W. B. DWIGHT. MACHINE FOR CUTTING 0R SLIGING MINERALS. No. 445,983. Patented Feb. 10,1891.

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'W. B. DWIGHT. MAGHINE FOR GUTTING OR SLIOING MINERALS. No. 445,983. Patented Feb. 10, 1891.

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W. B. DWIGHT. MACHINE FOR CUTTING OR SLIUING MINERALS. No. 445,983. Patented Feb. 10, 1891.

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MACHINE FOR CUTTING OR SLIGING MINERALS. No. 445,983. Patented Feb. 10,1891.

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No. 445,983. Patentec'i Feb.'10, 1891.

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W. B. DWIGHT. MACHINE FOR CUTTING OR SLIDING MINERALS. N0. 445,983. Patented Feb. 10,1891.

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W. B. DWIGHT; MACHINE FOR CUTTING ORSLIGING MINERALS. No. 445,983. Patented Feb. 10, 1891.

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"3 m a a: '0' I'll H1 1"" I u ET I I I 771%: m Z6 W Wm \VILLIAM I3. DW IGIIT, OF POUGHKEEPSIE, NEXV YORK.

MACHENE FOR CUTTING OR SLICING it'ilNERi-tLS.

SPECIFICATION forming part of Letters Patent No. 445,983, dated February 10, 1891.

Application filed September 18, 1890. Serial No. 365,321. (lie model.)

To all whom it may concern.-

Be it known that 1, WILLIAM B. DWIGHT, professor of na ural history, Vassar College, a citizen of the United States, residing at Poughkeepsie, in the county of Dntchcss and State of New York, have invented certain new and useful Improvements in Machines for Cutting and Slicing Minerals; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

The invention relates. broadly or generally speaking, to machines or apparatus for cutting or sawing stone, though the machine or apparatus hereinafter to be described is more especially designed for more delicate and accurate work than that done by the ordinary stone sawing or cutting machine.

Notwithstanding the fact that the machine which forms the subject-matter of this inveniion is more especially designed, as stated, for delicate and accurate work, yet it embodies improvements that are applicable generally to stone sawing or cutting machines, as well as to machines for cutting other substances in which discoidal cutters are employed either singly or in a gang.

The invention has for its object a machine or apparatus for sawing orcutting minerals and other hard substances into comparatively thin slabs or tablets for mosaic or similar work, as well as for educational and scientific purposes; to which ends the invention consists in structural features and in the combination of cooperative elements and mechanism, as will now be fully described, reference being had to the accompanying drawings, in which like letters indicate like parts wherever such may occur in the various figures.

Figure l is a general perspective View of an apparatus or machine for sectioning hard substances, illustrating as many of the co-operative mechanisms and other elements as ispossible and consistent with clearness. Such is an underside view of the table of the apparatus. Fig. 1 is a section thereof, taken on line 1 l of Fig. 1. Fig. 1 is a section of the lathe-bed, illustrating the bracket-bearing for the guide-pulleys for the drivingbelt; and Fig. 1 is a sectional detail view of the upper part of the standard A shown in Fig. 1. Fig. 2 is a front elevation of the work-holder, the support therefor, and the adjusting mechanism. Figs. 2 2 and 2 are sections taken, respectively, on lines 2 2, 3 3, and a of Fig. 2, the standard B being on1itted in Fig. 2. Fig. 3 is a right-hand elevation of the adjusting mechanism for the support of the work-holder, which latter is shown in section. Figs. 3 and 3 show by a face View and side elevation,respectively, amoditied construction of the support for the workholder. Figs. 3 and 3 are views similar to Figs. 3 and 3, illustrating a modification in the means for connecting the work-holder support with its adjustable carrier. Fig. 4 is a top plan view of the work-holder, the carriage, the means for adjusting the clampingjaws of the work-holder and a port-ion of the support therefor, and of the screw for adj nsting said work-holder longitudinally on the support. Fig. 4 is an end elevation of the worleholder and its carriage, the support for said holder and the screw for adjusting the same longitudinally on its support being shown in section. Fig. 4Q is a rear elevation of the work-holder. Fig. at is a vertical trans verse section of the work-holder, its carriage, the support therefor, and the adj Listing-screw. Fig. 4 is a rear elevation of the work-holder, the clamping-jaws being removed. Fig. 4 is a rear elevation of the carriage for the workholder; and Fig. 4'', Sheet 15, is a view similar to Fig. et showing a single right and left hand threaded ad j Listing-screw for the clamping-jaws. Figs. 5, 5, and 5 show the workholder and its carriage by a front and rear elevation and a central transverse sectional view, respectively, in conjunction with a modified adj Listing-gearing for revolving the work-holder on its carriage; and Figs. 5, 5 and 5 are detail views of the brake for said gearing. ons forms of auxiliary jaws. Fig. 6 is atop view of an auxiliary clamping-j aw for Objects too large to be clamped in the jaws of the Fig. 6 shows by end views vari work-holder. Figs. 6 and 6 are top plan views of parallel horizontal clamps combined with toothed auxiliary clamps, and Figs. 6 6, and 6 are detail views of the clampingframe shown in Fig. 6. Figs. 7, 7, 7, 7, 7, 7, 7 7*, and 7 show further means for securing substances of irregular form to the work-holder. Fig. 8 is an elevation of the cutter-spindle and means for supporting the same; and Figs. 8 and 8 are sections taken, respectively, on lines 5 5 and 6 6 of Fig.8; and Fig. 8 is a sectional view of the cutter-spindle carrying a plurality of cutters. Fig. 0 is a perspective view of one form of cutter leveling and guiding device, of which Figs. 9, 9, 9, and 9 are detail views. Fig. 10 is a top view of the cutter and leveling and guiding de vices adapted for use with a gang of cutters, and Fig. 10" is a front elevation thereof. Fig. 11 is a like view showing a modified construction of the leveling and guide arm. Fig. 11 is a top view of the guide-arm. Figs. 12 and 12 are elevations of a rim-guide for use with a single cutter or a gang of such, respectively; and Fig. 12 is a top plan view of the rim-guide shown in Fig. 1%.

The machine or apparatus whichI am about to describe being more particularly designed for very accurate as well as very delicate work, such as the cutting of extremely thin strips, slabs, or tablets for microscopic study or for mounting as specimens for mineral cabinets or collections for educationalinstitutions or museums, it will be understood that the various mechanisms, as well as the auxiliary devices, are constructed with that care and exactitude which is necessary to accurate operation, and which is generally found in scientific instruments or instruments of precision. It will, however, be understood that I do not limit myself to such a machine orapparatus, as the general improvements made are applicable to machines for coarser yet accurate work for various other purposes than those referred to.

Referring now more particularly to Figs. 1, 1, 1 and 1, F indicates the frame of the machine, which in general construction is that of an ordinary lathe-frame, of which f is the bed-plate, and f the treadle connected by rod f to the driving-shaft F, that carries the driving-pulley F which is constructed so as, have at least two portions or sections of different diameter in which the belt or cord grooves f y are formed. The driving-shaft F also carries a fast and loose belt-pulley F F, respectively, so as to adapt said shaft to be belted to and driven from any suitable prime motor instead of being driven from the treadle f.

To the bed-plate f of the frame is secured a bracket f in the pendent arms of which are formed the bearings for the journals of two grooved pulleys or sheaves F F, and F is the grooved pulley or sheave on the end of the vertical cutter-spindle S, driven by driving-wheel F through the medium of a cord or beltf, that passes around the wheel F in the groove f of the section or portion of least diameter, thence around the front guide-pulley F to and around pulley F on spindle S, and from the last-named pulley around the guide-pulley F and back to the groove f of the driving-wheel F From the left end of the bedf of the frame F projects a standard a, in the arms of which are formed the bearings for a horizontal spindle A, to which is secured a belt-pulley a, adapted to be belted to the driving-Wheel F, the belt or cord a lying in the groove f of that portion of the wheel which is of the greatest diameter. The spindle A is provided with a taper screw A and carries disks of felt a" orof analogous or equivalent material for polishing emery-wheelsa necessary accessory to a machine of this classand when the cutter spindle or spindles are driven by foot-power the belt a will be found of greatest convenience in starting the drivingshaft F. The driving-Wheel F should be sufficientl y heavy to act a fly-wheel, though, if desired, such a wheel may be provided and mounted on the shaft F at any desired or convenient point, especially if the machine is driven by a power other than the treadle.

To the bedplate f of the frame is secured a table T of such dimensions as to be capable of accommodating all the necessary 00- operative mechanisms, and for convenience of'access to the treadle f and other mechanisms the said table is secured to the bed-plate f so as to project but little beyond its front edge. This table T is of cast metal, its up per face being planed perfectly true and smooth, and is secured to the bed-plate so as to be perfectly level. The table T has depending edges or marginal flanges 25, and on its under side is provided with transverse strengthening-ribs 75, said edge or marginal flanges t and transverse ribs 25 being provided with interiorly-threaded sockets t for the reception of screw-bolts, by means of which said table is secured to the bed f of the frame.

To better sustain the weight of the rearwardly-projecting portion of the table a suitable brace or braces i may be secured thereto and to one or both of the legs of the frame, as shown in Fig. 1.

To the upper face of the table are secured marginal strips 25, that are made fluid-tight by any desired means, so as to retain the lubricant used and dropping onto the table, which at its rear left corner is provided with a hole 75 Fig. 1, for drawing off the lubricant or for allowing the same to flow off into a suitable receptacle, and also for the purpose of removing the detritus resulting from the cutting of mineral and other hard substances.

When the apparatus is used for less delicate or less accurate work, the table T, with its upwardly and downwardly projecting edge or marginal flanges and cross-ribs, may be cast in one piece.

I will, now describe the mechanism by means .to the inch.

of which the support for the work-holder is adjusted vertically relatively to the cutter or cutters and by means of which said support may be revolved on its axis or in a circular plane, referring to Figs. 1, 2, 2, 2 2, and

At the left end of the table T is secured a standard 13, the base-plate of which is provided with a step I) for the lower cone end of a vertical cylindrical steel bar B, whose upper cone end has its bearing in a conical recess formed in the end of a binding or set screw 1), that works in a screw-threaded opening formed in the upper horizontal arm 12 of standard B, said screw being held against accidental rotation by a jam or lock nut 0 Figs. 2 and 3, thus providing means for taking up wear of the mime-bearings of the bar B, as well as for securing the same against rotation in its bearings. The said bar has a longitudinal key-groove N, Fig. 2, for the reception of a key, spline, or feather Z)", that serves to lock a sleeve 13 against rotation on bar 13' without interfering with the vertical motion of said sleeve on the bar. At its upper end, below the horizontal arm I) of the standard B, the bar B carries a collar 13*, secured to said bar by means of a set-screw h, Figs. 2 and 3. In the said collar is formed an opening for the passage of a vertical adjusting screw B", that works in a screw-threaded hearing I)", formed on the sleeve B Figs 2 ant 2 and is revolved by means of a ballhandle Z2 secured to its upper end, Figs. 2 and 3, or by means of a hand-wheel, the screw being provided with an abutment or flange b (shown in dotted lines in Fig. 2,) that seats in a corresponding recess in the under side of the collar 13 and holds the said screw against endwise motion in the collar. For the purposes for which the apparatus under consideration is designed the screw 13* should have not less than thirteen (13) threads The sleeve B has an interiorlythreaded bearing b, Fig. 2 for a set-screw If", by means of which it may be locked against vertical motion on the bar B after being adjusted in order to relieve the adjust.- ing-screw B of the weight of said sleeve and the devices supported thereby, which weight is considerable, especially when com paratively large pieces or blocks of mineral or of other hard substances are tobe cut, and which would speedily wear away the threads of said screw. 0n the other hand, the set-screw b may not be brought into use when the substance to be cut is small and light; yet I preferably lock the sleeve-bearing to the bar in all cases, for the reason that there is always more or less vibration of the parts, due to the motion of the revoluble elements of the appa ratus, which vibration or jarring is apt to displace the adj ustiug-screw, and thereby change the position of the sleeve B In the cutting of minerals or other hard substances, especially if of irregular form, it is of great advautage-in fact, it isalmost absolutely necessary-to be able to present the substance to the cutter in the most advantageous manner in order to obtain specimen slabs, tablets, or strips that will show the structure or composition of the substance to the best advantage. This cannot always be effected by a more vertical adjustment of the work-holder and its support relatively to the cutter, for which purpose the mechanism just described is designed,the support fortheworkholderbeing connected with the sleeve Bi.

In order to accomplish the mostdesirable results, I provide means whereby the support for the work-holder maybe revolved about its axis or adjusted in a circular plane, and these means I will now describe, again referring to said Figs. 1, 2, 2, 3, and 3, and thereafter the means for adjusting the work-holder longitudinally on its support. The sleeve B has on its right side a disk or cylindrical boss I), to the periphery of which is secured by means of screws or bolts a bearing 0 for the journal or trunnion projecting from one side of a bearing 0, in which works a worm O, that is revolved by means ofahandle C. The journal of the bearing 0 is screw-threaded at its outer end, and is secured in its bearing 0' by means of the nut 0 Figs. 2 and 2, so that by loosening said nut the worm-bearing c and the worm-screw C may be swung out of gear with the worm-wheel D, when the support for the work-holder may be revolved by hand to expedite the adjustment of said workholder.

In the sleeve 13*, centrally of the cylindrical boss I) and extending nearly to the bore of said sleeve, is formed a horizontal bearing for the left end of the work-holder support. This support consists of a cylindrical steel bar D, whose left end fits snugly into the horizontal bearing formed in the sleeve B The bar D has a longitudinal key-groove d, which may be rectangular in cross-section for the reception of a like key, spline, or feather on the work-holder carriage, or said groove may be V-shaped in cross section for the reception of a like guide and locking-dog on said carriage, as hereinafter referred to. At said left end the work-holder support D carries the worm wheel D, above referred to,'in which is formed a segmental slot (1, Fig. 3, through which extends a locking or set screw (Z that screws into a holein the face of the cylindrical boss Z) of the bearing-sleeve B for the purpose of locking the support D and the worm-wheel D against rotation after being adjusted. As shown in Fig. 3, the slot din the worm-wheel admits of one-half of a revolution of the supthe bearing I a washer (Z is interposed between the head of the screw and the outer face of the worm-wheel. For the purpose for which the apparatus is more particularly designed the worm C and the worm-wheel I) should have a thread sufficiently fine to admit of a verydelicate adjustment of the support I).

If heavy substances are to be cut, in order to bring the weight thereof nearer to the center of rotation, the support D may be provided with a crank (1, Figs. 3 and 3 or the wormwheel I) may be provided with a journal (1, adapted to fit the horizontal bearing in the sleeve B and the support D may be secured eccentrically to the said worm-wheel D, as shown in Figs. 3 and 3. In the last-named construction the thickness of the worm-wheel may be considerably increased in order to give it the necessary strength to support the bar D and the elements carried thereby. Inasmuch, however, as the support D is detachably connected with the bearing-sleeve B the several supports D, suited to the nature of the work to be done, may be interchangeably connected with said bearing, the diameters of the various worm-wheels being of course the same, though even this may vary within'the limits of adjustment of the worm O in its bearing 0. On the other hand, for very heavy work the support D may be braced at any convenient point either by a brace on the table or a hanger suspended from a fixed support above the apparatus, either of which should be adjustable.

For the purpose of adjusting the workholder along its support D, the latter carries the collars D D adapted to be rigidly connected with said support by means of setscrews (1, and each of said collars has abearing for the opposite ends of a horizontal adjusting-screw D, that carries at its outer end a ball-handle or hand-wheel D which should be sufficiently remote from the collar D to admit of its manipulation when the workholder is at the extreme limit of its movement to the right.

If desired, the stem of the handle or handwheel may be provided with a squared socket adapted to tit upon a squared outer portion of the screw D, so that it may be removed from the ad justing-screw D when not in use, as shown in dotted lines in Fig. 2. The screw D has also an abutment or collar (1 that fits into a recess in the left face of the collar D to hold the said screw against endwise motion.- The screw D- works in an interiorlythreaded lug e on the back of the slide or carriage E for the work-holder, and said screw, like screw 13, should have not less than thirteen (13) threads to the inch. For light work the collar D that supports the left end of the screw D", may be dispensed with, as the collar D and the lug on carriage E will hold said screw sufficiently steady for the purposes of adjustment of said carriage on the support 1). It will be observed that both collars D and D are detachable from the support D for the convenience of dismembering the parts. It is obvious, however, that these collars could form an integral part of the support D.

To avoid the necessity of moving the support D for the work-holder by hand to the cutter as the cutting proceeds, I employ aspringA", that has a hook at one end adapted to be hooked to the adj usting-screw D. The opposite end of the spring is attached to a cord a, that passes over a pulley a on a standard A, the free end of the cord being attached to a rod a, adapted to carry a weight or weights A, thus providing a feeding de- -vice adapted to hold the substance to be cut to the cutter with a yielding pressure. The cord a may, if desired, be attached to a lever carrying a weight adapted" to be adjusted thereon toward and from the lever-fulcrum for the purpose of regulating the tension of the spring.

I will now describe the construction of the work-holder and its carriage, as well as the construction and arrangement of the means for connecting the same with and revolving it on its carriage, the interchangeable clamping-jaws of the work-holder, the means for connecting the same to the jaws of said workholder, and the mechanism for adjusting the clamping-jaws on the carriage relatively to the object to be held thereto, as well as adjuncts for more securely holding said object between the jaws, reference being had to Figs. 1 and 2, and to Figs. 4 to 7- As hereinabove described, the carriage E is held against rotary motion on the support D by a key, spline, or feather, which may be of rectangular form in cross-section. It is desirable, however, that means other than the screw D should be provided for locking the work-holder carriage into the position to which it is adjusted on its support with a View to relieving the threads of the screw from any strain due to vibration. To this end I preferably provide thesupport D with a guide-groove d, that is V-shaped in cross-section, and I employ a set-screw e, that has a correspondinglyshaped head 6 at its end, Fig. 4, or the said set-screw may bear upon a key inserted into and of the shape of the groove. By this means the carriage E is not only properly guided on the support D, but can be locked thereto, and ,he wear of the parts taken up to keep the carriage steady in its movements. In practice, however, I prefer to employ an additional binding or set screw 6 Figs. 2, 4, 5, and 5, for locking the carriage to the support D. The carriage E consists, essentially, of a cylindrical portion E, 011 the rear face of which is formed a tubular or sleeve bearing a, through which passes the support D, and on said sleeve 6" is formed theinteriorly-threaded bearing 6, in which works the adjusting-screw D", as shown in Figs. 2, 4, 4, 4, 5, and 5 On the periphery of the cylindrical portion E is formed or secured a plate 6 in Whichis formed a bearing for the journal 6 of a pinion E which journal may or may not form an integral part of the pinion,and may be socured in its bearing so as to revolve freely therein in any well-known or desired manner. It is desirable, however, that these parts should be so constructed as to be readily removed and as to provide for the taking up of wear, and to this end I preferably construct the parts as follows and as shown in Fig. 4: The pinion E has an axialopening and in its front face an annular recess formed around said opening for the reception of the head of a lockingscrew 6 that screws into an axial opening of a journal 6, provided at its rear end with an abutment or lockingtlange e and with a squared extension 6 for the purpose of holding the journal against rotation in its bearing while the screw is 1nanipulated and to revolve the pinion for adjusting the jaws, said journal being provided with a spline, key, or feather to lock the pinion E against rotation.

In an apparatus of the kind under consideration the work-holder should be of such a construction as to receive and firmly hold substances whatever theirform and texture, and in this class of apparatus great difliculties-in fact, insurmountable difficultieshave heretofore been encountered in securing small and fragile specimens or specimens of loose texture or of little tenuity with sufficient firmness in the work-holder for sectioning the same; nor has it been possible with the means at hand in apparatus as heretofore constructed to secure substances of irregular form in the most advantageous position for sectioning the same, as it frequently happens that a substance can be held in the workholder in only one or two positions in order to admit of a ti rm prehension of the clamping devices without crushing the substance or its edges, while either of these positions may be impracticable or disadvantageous in the cutting of sections therefrom in a desired plane.

The want of proper means for holding substances of irregular form in the most desirable and advantageous position for obtaining sections thereofas, for instance, a thin slab to be cut parallel with its face, 01 more or less cylindrical or conoidal bodies to be bisected in the plane of the longest axis of such bodies-entails losses in material as well as tedious labor, as such bodies have heretofore been presented to the cutters by hand, if not too small, or secured in an ordinary carpenters or joiners clamp held by hand to the cutters, so that a perfectly true section could not be obtained. The devices which I am about to describe are designed to obviate these difficulties and provide means whereby bodies of almost every form, texture, and dimensions within certain limits maybe firmly held in the work-holder in the most desirable or advantageous position for sectioning the same.

The workholder is composed of two jaws G G, that are adapted to slide on Ways g, formed on a supportingplate G, Figs. 4, 4i,

-l", 49, I, 5, and 5 whose length determines the extent to which the jaws G maybe moved from each other. This plate G is secured to a gear-wheel E that is in gear with pinion E above referred to, said gear-wheel E being mounted on a journal secured to the carriage E. In ordertodetachably connect these drical portion E of the carriage E. In order to give greater steadiness to the work-holder in its revolving movements and to more firmly connect it with the carriage E, the wheel E has on its front face a cylindrical boss e formed around its axial aperture, which boss fits into a corresponding recess formed in the front face of the cylindrical boss E of carriage E, Fig. 4. It is obvious that when the pinion is rotated the workholder will be revolved in an opposite direction, thus providing an additional and important adjustment to present the object operated upon in the most desirable position to the cutter or cutters, and important also in adjusting the work-holder to the plane of the cutter. As shown in Fig. et the journal g for the wheel E is of such a length as to project slightly beyond the face of the cylindrical boss 8 0f the wheel E so that said wheel cannot be rigidly locked to the carriage. By the means described the work-holder may be adjusted with fair precision by revolving it on its axis; but when very delicate work is to be done which requires a very delicate adjustment I prefer to employ worn'l-ge-aring instead of the ordinary gearing above described, as shown in 5, 5, and 5 thepinion E being here replaced by a worm E and the wheel E by a worm-wheel E, the worm being secured to its bearing in the manner as described in reference to the worm 0, Figs. 2, 2, and 3, and needs, therefore, no further description.

In either form of adjusting-gearing it is necessary that means be provided to lock said gearing against rotation after the work-holder has been adjusted. To this end I employ a brake-shoe g, Figs. l, 5, 5, 5, 5 and 5 This brake-shoe consists of a block of brass or other suitable material, the under face of which is of curvilinear form to fit the periphery of the wheel or that part of the wormwheel E and is secured to or forms part of a rectangular bracket 9', the pendent arm of which extends ov r the front face of the cylindrical boss E of the carriage E, to the periphery of which bossthe bracket is secured by means of an adj listing-screw P, so that by 

